Author(s): Oscar Castro-Orgaz (IAHR Member); Willi H. Hager (IAHR Honorary Member)
Keywords: Boussinesq model; gate; hydraulics; open channel flow; transitional flow
Abstract: Gates are one of the most important hydraulic structures extensively investigated by physical and two-dimensional (2D) numerical research in the past. However, the hydraulics of free gate flow features of engineering interest, including the water surface profile, the force on the gate, or the bottom pressure distribution, were overlooked in the literature, so that the current knowledge is incomplete. In this work this gap is filled in using a higher order one-dimensional model based on a Boussinesq-type closure. The proposed model provides the free surface profile of the approach flow as a cnoidal wave, and the free jet portion as a generalized solitary wave, which compare well with 2D results. The model further provides as a part of the theoretical computation the pressure distribution on the gate. Bottom pressure features were also determined resulting in a good agreement with potential flow data. Boussinesq-type equations for submerged jets are presented and solved for the submerged hydraulic jump.